Participate in disaster relief efforts where Internet infrastructure is unreliable

OpenStreetMap itself is open data, so if you have advanced needs not served by existing tools and services, you are also free to download and process the data yourself without making repeated requests to the OpenStreetMap API.

Multi-user offline editing

One challenge with offline editing is that a downloaded area can become out of date, so that by the time you make your edits and upload them, conflicts arise with intervening edits by other mappers. This problem is exacerbated in scenarios such as disaster relief, where many people need to contribute to the same part of the map in tandem while offline. The Portable OpenStreetMap (POSM) project, with its POSM Replay Tool, aims to address this issue by implementing a version control system for offline edits and proper merging afterwards.

Limitations

Quickly serving huge volumes of raster or vector tile data can incur a significant cost to map providers. Therefore, even free-of-cost services usually limit the number of tiles you can download, the rate at which you can download them, or the geographic area or level of detail that you can download. If you download tiles from the OpenStreetMap website or API, please see our Tile usage policy. Otherwise, please respect the restrictions imposed by the tool or service you choose.